. Author manuscript; available in PMC: 2015 Jun 1.

Published in final edited form as: Cancer Epidemiol Biomarkers Prev. 2014 May 16;23(6):1055–1066. doi: 10.1158/1055-9965.EPI-13-0939

Table 3.

Cross correlations between changes in biomarkers^a

	COT_Δ₁	COT_Δ₂	NIC_Δ₁	NIC_Δ₂	NNAL_Δ₁	NNAL_Δ₂	2HPMA_Δ₁	3HPMA_Δ₁	AAMA_Δ₁	CNEMA_Δ₁	MHBMA_Δ₁	HEMA_Δ₁	PMA_Δ₁
COT_Δ₁	l	0.90^***	0.19	0.44^***	0.73^***	0.75^***	–0.04	0.29^*	0.74^***	0.84^***	0.10	0.65^***	0.92^***
COT_Δ₂		1	0.09	0.51^***	0.71^***	0.78^***	–0.08	0.23	0.73^***	0.86^***	0.09	0.67^***	0.92^***
NIC_Δ₁			1	0.52^***	0.09	0.12	–0.17	0.18	0.06	0.08	0.06	0.23	0.01
NIC_Δ₂				1	0.59^***	0.66^***	–0.01	0.42^**	0.53^***	0.43^***	0.09	0.31^*	0.35^**
NNAL_Δ₁					1	0.94^***	0.34^**	0.36^**	0.76^***	0.70^***	0.08	0.33^*	0.64^***
NNAL_Δ₂						1	0.09	0.42^**	0.86^***	0.79^***	0.10	0.44^***	0.69^***
2HPMA_Δ₁							1	–0.10	–0.03	–0.13	–0.07	–0.34^*	–0.10
3HPMA_Δ₁								1	0.27^*	0.24	0.16	0.24	0.35^**
AAMA_Δ₁									1	0.85^***	0.09	0.45^***	0.68^***
CNEMA_Δ₁										1	0.12	0.64^***	0.82^***
MHBMA_Δ₁											1	0.30^*	0.14
HEMA_Δ₁												1	0.70^***
PMA_Δ₁													1

All subjects included in the analysis; COT = cotinine; NIC = nicotine; NNAL = 4–(methylritrosamino)–1–(3–pyridyl)–1–butanol; VOC mercapturic acid metabolites (parent compound in parenthesis): 2HPMA=2-hydroxypropyl (propylene oxide), 3-HPMA=3-hydroxypropyl (acrolein), AAMA=2-carbamoylethyl (acrylamide), CNEMA=cyanoethyl (acrylonitrile), MHBMA=2-hydroxy-3-buten-1-yl or isomer(s) (1,3-butadiene), HEMA=2-hydroxyethyl (ethylene oxide), and PMA=phenyl (benzene);

Δ₁ = post minus pre-exposure; Δ₂ = nextday minus pre-exposure; VOC mercapturic acid metabolites were only measured in pre-exposure and post-exposure samples;

p < 0.05

^**

p < 0.01

^***

p < 0.001